In current communication system, some specific traffic type, like guaranteed bit rate (GBR) traffic, should be prioritized. The GBR traffic may include traffic of IP (i.e., Internet protocol) multimedia subsystem (IMS) services such as multi media telephony (MMTEL) video/voice or short message service (SMS) traffic. Generally speaking, the GBR traffic usually has higher Quality of Service (QoS) level than non-GBR traffics. However, in current 3rd generation partnership project (3GPP) specifications, the network could guarantee higher QoS level for the GBR traffic only after the IMS connection has been successfully established between user equipment (UE) and the network. Otherwise, the network cannot prioritize the GBR traffic while establishing the IMS connection.
To resolve this issue, the working item (WI) called “New Work Item Proposal on Smart Congestion Mitigation in E-UTRAN” was discussed in 3GPP. This WI was about how to prioritize the GBR traffic, like MMTEL video/voice and SMS traffic, before successfully establishing the IMS connection. After the WI discussion, the access class barring (ACB) skip mechanism was proposed to resolve the issue. In the ACB skip mechanism, the network could control which type of the GBR traffic (e.g., MMTEL video/voice or SMS traffic) could skip the ACB check. In this way, some of the GBR traffic could skip the ACB check to have higher priority to access the network. However, how to prioritize GBR traffic on random access (RA) procedure was not discussed in the WI.
Since the network could prioritize some of the GBR traffics at network access procedure by ACB skip mechanism, the network still needs more info illation to decide when and how to perform the specific access control mechanism. In addition, if the network has more information about the access state of the GBR traffic, it could understand the potential GBR traffic distribution by statistics thereof and perform appropriate control mechanism to guarantee the QoS level of the GBR traffic.